Assignment #5 - An Open Assignment with Several Default Choices

Submit a project proposal by April 15 (Monday).

Demo on April 29 (Monday), April 30 (Tuesday), or May 1 (Wednesday).

Assignment Contact: If you work on one of the default choices, you should direct all your questions to the TA (Amal). If you design a new assignment outside of the default choices, your contact person is the instructor (Kai). Regardless who your assignment contact is, you should always sign up your demo slot with the TA.

This is an open choice assignment. You can choose from four default choices that are given below. But you can also design a brand-new assignment on something that you have particular interests in. If this is what you want, please inform the instructor as soon as possible. If needed, the instructor may help you to define a specific project scope. Any idea can be considered as long as the topic is substantially related to computer networks.

For this assignment, you can choose to work in a team of two if the scope justifies that. If you are not sure if your project warrants a two-person group, please contact the instructor.

In some projects, you will need to work on a wide-area network testbed. If this applies to you, you should arrange with the instructor to set up an account on the PlanetLab testbed.

Demo:
You need to set up a 30-minute demo with the TA. We will open up the demo signup process after the proposal due date. In the demo you need to show us how your project works (or partially works) with your own test cases. (Prepare the testing cases before the demo!) We may ask you to run some of our own test cases and ask some questions about your design & implementation. If you work on one of the default choices, then you should demo on April 29 (Monday) or April 30 (Tuesday). If you work on a special-design assignment, then your demo will be on May 1 (Wednesday).

Turn-in:
By April 15 (Monday), you need to submit (using the electronic turn-in) a project proposal. We will not grade the proposal but we need to see evidence that you have started working on it by that time. In the proposal, you should describe a concrete goal of your project, any related materials (papers and web resources) you have read, and anything else you feel relevant. Please keep the proposal within two pages. You need to submit a proposal even if you choose one of the default assignment choices. We only provide rough descriptions for them here and your proposal should list more concrete project goal. The project proposal should be in the PDF format. And note that all turn-ins are done through the electronic turn-in facility. Do NOT send us email attachments.

By the time of your demo, you should turn in your source files, a makefile if needed, and a project report. The project report should clearly describe your overall design, any implementation detail that you deem interesting, how your programs should be compiled and run, and what each member of your group has done. When appropriate (for some assignments), your report should also describe the analysis result for the assignment. In addition to electronically turning in the project report, please also prepare a printed copy at the demo time.

The rest of this page describes the default assignment.

Choice 1: Query Sniffing and Analysis in Gnutella Network
You first need to get a machine in the department lab connected to the global Gnutella Network. Then you need to monitor all the queries forwarded to your machine. Last but not least, after you record a large number of queries, you need to analyze them (using whatever method) and find out if there is any interesting information you can extract from them. For example, do the queries follow any patterns? 50% of your grade will be based on the results/findings of your analysis.

Choice 2: Wide-area Network Bandwidth Measurement
Your task is to develop a tool to measure the network bandwidth between any two nodes in the wide-area network. Your tool should tolerate the unstable nature of wide-area networks. In other words, although the network itself is not stable (with packets loss and cross traffic that affects your measurements), the measured bandwidth between the same two nodes should NOT diverge too much during different runs of your tool and it should correspond well to the actual available bandwidth between the two nodes.

References:

  1. R. L. Carter and M. E. Crovella. Measuring Bottleneck Link Speed in Packet-Switched Networks. Technical Report BUCS-96-006, Computer Science Department, Boston University, March 1996.
  2. V. Paxson. End-to-End Internet Packet Dynamics. In Proc. of the ACM SIGCOMM, pages 139-152, Cannes, France, September 1997.
  3. K. Shen. Structure Management for Scalable Overlay Service Construction (Section 3.2). In Proc. of the First USENIX/ACM Symposium on Networked Systems Design and Implementation (NSDI'04), Pages 281-294, San Francisco CA, March 2004.

Choice 3: Implementation of a Multi-cast Routing Protocol based on RPF and pruning
The requirements are similar to those of Assignment #2, but instead of a unicast routing protocol, you should implement:

  1. A simple mechanism for hosts to join a multicast group.
  2. The reverse path forwarding with pruning protocol to deliver mcast-addressed packets to all hosts that have joined that multicast group.
You can test this assignment using the lab machines.

Choice 4: Web Data Crawling and Collecting
You are asked to build a Web crawler capable of operating in two modes: 1) run at a rate of N pages/second; 2) run at a rate of N bytes/second. With a given starting Web page, your crawler should crawl that page, then follow its hyperlinks to crawl more pages and so on. It should recursively follow the hyperlinks until you stop it or there is no more linked pages to read. In the demo, we will randomly specify a starting page. You should be very carefully in controlling the bandwidth your crawler may use. To avoid undesirable impact on other Web sites, you should not test on pages outside the department until you are quite sure that your program can run properly in the two required modes. After you fetch the pages, you should save them to the local hard drive, e.g., a sub-directory in the "/tmp" partition. Please delete them after you are done with your tests.

Warning: there are some web sites that do NOT welcome crawlers. Before your program tries to crawl on a web site (e.g., www.google.com), it should check if there is a robots.txt file on that site (e.g., www.google.com/robots.txt). See the Robot Exclusion Standard for more information about how robots.txt works.